Cancellation of Collisional Frequency Shifts in Optical Lattice Clocks with Rabi Spectroscopy

TL;DR

This paper proposes an over-$pi$ pulse scheme to cancel collisional frequency shifts in optical lattice clocks, achieving a fractional uncertainty of 10^{-18} by analytically and experimentally addressing s- and p-wave collision effects.

Contribution

It introduces a novel over-$pi$ pulse method combined with low inhomogeneity to eliminate collisional shifts in optical lattice clocks.

Findings

Analytical solution of collisional shifts as a function of pulse area and inhomogeneity.

Experimental validation with Yb optical lattice clock data.

Achieved fractional uncertainty of 10^{-18} in clock accuracy.

Abstract

We analyze both the s- and p-wave collision induced frequency shifts and propose a over-$\pi$ pulse scheme to cancel the shifts in optical lattice clocks interrogated by a Rabi pulse. The collisional frequency shifts are analytically solved as a function of the pulse area and the inhomogeneity of the Rabi frequencies. Experimentally measured collisional frequency shifts in an Yb optical lattice clock are in good agreement with the analytical calculations. Based on our analysis, the over-$\pi$ pulse combined with a small inhomogeneity below 0.1 allows a fractional uncertainty on a level of $10^{-18}$ in both Sr and Yb optical lattice clocks by canceling the collisional frequency shift.